It is often desirable to be able to cause an event to occur using remote control. By way of example, much of the present disclosure will refer to the event being the opening or closing of a door, gate or industrial shutter. However, the present disclosure is applicable to many other remotely-controlled events, and additional examples are provided.
In the case of an industrial shutter, for example at a loading bay entrance of a warehouse, it is often desirable for a user to be able to open or close the shutter by remote control. For example, the user may be driving a vehicle and, as he approaches the shutter, he may find that the shutter is closed. Operation of the shutter by remote control saves the user the inconvenience of stopping his vehicle, disembarking from it, opening the shutter, getting back into the vehicle and then driving further. Thus, the user saves time and, if it is raining, does not get wet. He is also able to remain safely inside his vehicle, which keeps him from potential danger, and means that the vehicle and contents are not left unattended.
There are two main types of known remote control systems suitable for opening a door, shutter or gate, etc. The first type, which may be referred to as “local” remote control, operates by sending a wireless (e.g. infra-red or radio frequency) signal from a handheld transmitter (or a transmitter mounted within a vehicle) to a receiver which is connected to door opening equipment (e.g. a motor). Such “local” systems have the disadvantage that every user needs a dedicated transmitter, and also the user needs to be in relatively close proximity to the door to be opened, in order for the door opening signal to be able to reach the receiver. Close proximity to the door is also necessary to enable the user to see whether the door is already open—in which case there would be no need for him to open it. Another disadvantage of “local” remote control systems is that no information can be sent back to the user, as the receiver-side apparatus does not include a transmitter.
The second type, which may be referred to as “network-based” remote control, uses a telecommunications network to transmit an instruction from the user to the door opening equipment, to cause the door to open. A commercially available example of such a system is available from DPS-Promatic srl, via Edison 21, 47100 Forlì, Italy, and is marketed under the name “Easygate” (www.dpspro.com/easygate.html). The Easygate system enables a user to open a gate using a mobile telephone. With the Easygate system, a GSM (Global System for Mobile Communications) receiver having a SIM (Subscriber Identity Module) is connected to control circuitry and a door opening motor. In use, a user uses a phone (which may be a mobile telephone, although not necessarily so) to dial the telephone number which corresponds to the SIM number of the system's GSM receiver. By dialling this number, the user causes a connection request to be sent to the system's GSM receiver. To save the user the cost of a phone call (in many countries), the Easygate system does not answer this incoming connection request, but instead instantly rejects the connection request. The Easygate system determines if the phone number of the user's phone is on a list of authorised numbers, and if it is, the system opens the door.
When the user dials the number of the Easygate system, the system does not provide the user with any confirmatory feedback via the telephone network, or any information regarding the status of the system. Having dialled the number, the user does not know whether the gate is being opened, or whether the gate is, for some reason, already open. The Easygate system is designed only to be used to open a gate, and not to close it, since by the system only acting to open the gate the Easygate user is provided with certainty that, after the Easygate number has been dialled, the gate will either be opened or will already be open.
The absence of any feedback with the Easygate system also means that, in practice, a user will tend not to use the Easygate system unless he is already within eyeshot of the gate to be opened, since this enables the user to see whether the gate is already open, before deciding whether it is necessary to use the Easygate system. Moreover, if he does use the system, being within eyeshot of the gate enables him verify that the gate has been successfully opened, and that no obstacle (or even a person) is in the way.
Accordingly, there is a desire for a network-based remote control system that can be used both to open and to close a door or the like, and which provides the user with some kind of feedback to confirm the remote action the system is performing.